Paper-making with straw is popular in our country, while it is mainly made from wood pulp at abroad. In a long run, non-wood fiber is used as the main raw material in our country's paper-making industry and straw pulp accounts for 80% of the raw material of paper-making. Especially in the provinces in the north of China, the resource of wheat straw is rich and its price is low, which become our superiority to make paper with straw. At present, the main processes to make pulp from straw are soda process, sulfate process, ammonia process and so on. Among them sodium hydroxide process is the process in common use. The fatal defects of conventional pulping technology are to produce large volume of black liquor which pollutes environment seriously and is very difficult to treatment. Many domestic and foreign experts intend to solve this problem for years, but fail to find a satisfied solution. At present, a well-known solution is to recover sodium hydroxide. However, the initial investment for sodium hydroxide recovering is too big for common enterprise to bear. Moreover, this process can not solve the problem completely yet.